package com.atguigu.stack;

import java.util.Scanner;

public class ArrayStackDemo {
    public static void main(String[] args) {
        ArrayStack stack = new ArrayStack(4);
        String key=" ";
        boolean loop=true;
        Scanner scanner = new Scanner(System.in);
        while (loop){
            System.out.println("show: 表示显示栈");
            System.out.println("push: 表示入栈");
            System.out.println("pop: 表示出栈");
            System.out.println("exit: 退出程序");
            System.out.println("请输入你的选择：");
            key=scanner.next();
            switch (key){
                case "show":
                    stack.list();
                    break;
                case "push":
                    System.out.println("请输入一个数：");
                    int value = scanner.nextInt();
                    stack.push(value);
                    break;
                case "pop":
                   try {
                       System.out.printf("出栈的数据：%d \n",stack.pop());
                   }catch (Exception e){
                       System.out.println(e.getMessage());
                   }
                    break;
                case "exit":
                    loop=false;
                    scanner.close();
                    break;
            }

        }
        System.out.println("退出程序");
    }
}
class ArrayStack{
    private int maxSize;
    private int[] stack;
    private int top =-1;

    public ArrayStack(int maxSize) {
        this.maxSize = maxSize;
        stack=new int[this.maxSize];
    }

    public boolean isFull(){
        return top == maxSize-1;
    }
    public boolean isEmpty(){
        return top == -1;
    }

    public void push(int value){
        if(isFull()){
            System.out.println("栈满");
            return;
        }
        top++;
        stack[top]=value;
    }

    public int pop(){
        if(isEmpty()){
            throw new RuntimeException("栈空了");
        }
        int value=stack[top];
        top--;
        return value;
    }

    public void list(){
        if(isEmpty()){
            System.out.println("栈空");
            return;
        }
        for (int i=top;i>=0;i--){
            System.out.printf("stack[%d]=%d\n",i,stack[i]);
        }
    }

}
